Indolyl-3-glyoxylic acid derivatives having antitumor action

ABSTRACT

The invention relates to the use of N-substituted indole-3-glyoxylamides of the general formula I as antitumor agents 
                         
and to a pharmaceutical composition having antitumor action, characterized in that it contains at least one of the compounds of the general formula 1, if appropriate also in the form of the physiologically tolerable acid addition salts or N-oxides. Furthermore, the invention also includes antitumor agents comprising as active compound one or more N-substituted indole-3-glyoxylamides according to the general formula 1 and, if appropriate, their physiologically tolerable acid addition salts and, if possible, N-oxides and a pharmaceutically utilizable carrier and/or diluent or auxiliary substance in the form of tablets, coated tablets, capsules, solutions for infusion or ampoules, suppositories, patches, powder preparations which can be employed by inhalation, suspensions, creams and ointments.

This is a continuation of U.S. patent application Ser. No. 09/810,604, filed Mar. 19, 2001, now abandoned which is a continuation of U.S. patent application Ser. No. 09/285,058, filed Apr. 2, 1999, now U.S. Pat. No. 6,232,327, issued May 15, 2001, which claims priority to German Patent Appl. DE 198 14 838.0, filed Apr. 2, 1998.

Indole-3-glyoxlamides have a variety of uses as pharmacodynamically active compounds and as synthetic building blocks in pharmaceutical chemistry.

In the patent application Neth. Appl. 6502481, compounds are described which have an anti-inflammatory and antipyretic activity profile and analgesic activity.

In the British Application GB-B 1 028 812, derivatives of indolyl-3-glyoxylic acid and their amides are used as analgesic, anticonvulsant and β-adrenergic compounds.

G. Domschke et al. (Ber. 94, 2353 (1968)) describes [sic]3indolylglyoxylamides which are not characterized pharmacologically.

E. Walton reports in J. Med. Chem, 11, 1252 (1968) on indolyl-3tive-glyoxylic acid derivatives which have an inhibitory action on glycerophosphate dehydrogenase and lactate dehydrogenase.

In the European Patent Specification EP 675110, 1H-indole-3-glyoxylamides are described which are profiled as sPLA2 inhiditors and are used in the treatment of specific shock, in pancreatitis and in the treatment of allergic rhinitis and rheumatoid arthritis.

The aim of the present invention is to make available N-substituted indole-3glyoxylamdies which have an anititumor action and thus to enrich the available pharmaceutical wealth.

The compound mentioned have already been disclosed as medicaments having antiasthmatic, antiallergic and immunosuppressant/immunomodulating action in DE-A 19636150 A1.

The invention therefore relates to the use of N-substituted indole-3-gloxylamides [sic] of the general formula 1 for the production of antitumor agents, antitumor agents having a content of active substance according to formula 1 and their use for the treatment of oncoses.

where the radicals R, R₁, R₂, R₃, R₄ and Z have the following meaning:

-   R=hydrogen, (C₁-C₆)-alkyl, where the alkyl group can be mono- or     polysubstituted by the phenyl ring and this phenyl ring for its part     can be mono- or polysubstituted by halogen, (C₁-C₆)-alkyl, (C₃-C₇)     -cycloalkyl, by carboxyl groups, carboxyl groups esterified with     C₁-C₆-alkanols, trifluoromethyl groups, hydroxyl groups, methoxy     groups, ethoxy groups, benzyloxy groups and by a benzyl group which     is mono- or polysubstituted in the phenyl moiety by (C₁-C₆)-alkyl     groups, halogen atoms or trifluoromethyl groups, -   R is further the benzyloxycarbonyl group (Z group) and the     tertiary-butoxycarbonyl radical (BOC radical), furthermore the     acetyl group. -   R₁ can be the phenyl bring, which is mono- or polysubstituted by     (C₁-C₆)-alkyl, (C₁-C₆)-alkoxy, cyano, halogen, trifluoromethyl,     hydroxyl, benzyloxy, nitro, amino, (C₁-C₆)-alkylamino,     (C₁-C₆)-alkoxycarbonylamino and by the carboxyl group or by the     carboxyl group esterified with C₁-C₆-alkanols, or can be a pyridine     structure of the formula 2 and its N-oxide [sic]

-   -   and its N-oxide, where the pyridine structure is alternatively         bonded to the ring carbon atoms 2, 3 and 4 and can be         substituted by the substituents R₅ and R₆. The radicals R₅ and         R₆ can be identical or different and have the meaning         (C₁-C₆)-alkyl and the meaning (C₃-C₇)-cycloalkyl,         (C₁-C₆)-alkoxy, nitro, amino, hydroxyl, halogen and         trifluoromethyl and further are the ethoxycarbonylamino radical         and the group carboxyalkyloxy in which the alkyl group can have         1-4 C atoms.

-   R₁ can further be a 2- or 4-pyrimidinyl heterocycle, where the     2-pyrimidinyl ring can be mono- or polysubstituted by the methyl     group, furthermore are [sic] the 2-, 3-, and 4- and 8-quinolyl     structure substituted by (C₁-C₆)-alkyl, halogen, the nitro group,     the amino group and the (C₁-C₆)-alkylamino radical, are [sic] a 2-,     3- and [sic] 4-quinolylmethyl group, where the ring carbons of the     pyridylmethyl radical of the quinolyl group and of the     quinolylmethyl radical can be substituted by (C₁-C₆)-alkyl,     (C₁-C₆)-alkoxy, nitro, amino and (C₁-C₆)-alkoxycarbonylamino.

-   R₁, in the case in which R=hydrogen, the methyl or benzyl group and     the benzyloxycarbonyl radical (Z radical), the tert-butoxycarbonyl     radical (BOC radical) and the acetyl group, can furthermore be the     following radicals:

—CH₂COOH; —CH(CH₃)—COOH; —(CH₃)₂—CH—(CH₂)₂—CH—COO—; H₃C—H₂C—CH(CH₃)—CH(COOH)—; HO—H₂C—CH(COOH)—; phenyl-CH₂—CH(COOH)—; (4-imidazolyl)—CH₂—CH—(COOH)—; HN═C(NH₂)—NH—(CH₂)₃—CH (COOH)—; H₂N—(CH₂)₄—CH(COOH)—; H₂N—CO—CH₂—CH—(COOH)—; HOOC—(CH₂)₂—CH(COOH)—;

-   R₁, in the case in which R is hydrogen, the Z group, the BOC     radical, the acetyl or the benzyl group, can furthermore be the acid     radical of a natural or unnatural amino acid, e.g. the α-glycyl, the     α-sarcosyl, the α-alanyl, the α-leucyl, the α-isoleucyl, the     α-seryl, the α-phenylalanyl, the α-histidyl, the α-prolyl, the     α-arginyl, the α-lysyl, the α-asparagyl and the α-glutamyl radical,     where the amino groups of the respective amino acids can be present     unprotected or can be protected. A possible protective group of the     amino function is the carbobenzoxy radical (Z radical) and the     tert-butoxycarbonyl radical (BOC radical) as well as the acetyl     group. In the case of the asparagyl and glutamyl radical claimed for     R₁, the second, unbonded carboxyl group is present as a free     carboxyl group or in the form of an ester with C₁-C₆-alkanols, e.g.     as a methyl, ethyl or as a tert-butyl ester.     -   Furthermore, R₁ can be the allylaminocarbonyl-2-methylprop-1-yl         group.     -   R and R₁ can further form, together with the nitrogen atom to         which they are bonded, a piperazine ring of the formula III or a         homopiperazine ring, provided R₁ is an aminoalkylene group, in         which

-   -   R₇ is an alkyl radical, is a phenyl ring which can be mono- or         polysubstituted by (C₁-C₆)-alkyl, (C₁-C₆)-alkoxy, halogen, the         nitro group, the amino function and by the (C₁-C₆)-alkylamino         group. R₇ is furthermore the benzhydryl group and the         bis-p-fluorobenzylhydryl [sic] group.

-   R₂ can be hydrogen and the (C₁-C₆)-alkyl group, where the alkyl     group is mono- or polysubstituted by halogen and phenyl, which for     its part can be mono- or polysubstituted by halogen, (C₁-C₆)-alkyl,     (C₃-C₇)-cycloalkyl, carboxyl groups, carboxyl groups esterified with     C₁-C₆-alkanols, trifluoromethyl groups, hydroxyl groups, methoxy     groups, ethoxy groups or benzyloxy groups. The (C₁-C₆)-alkyl group     counting as R₂ can further be substituted by the 2-quinolyl group     and the 2-, 3- and 4-pyridyl structure, which can both in each case     be mono- or polysubstituted by halogen, (C₁-C₄)-alkyl groups or     (C₁-C₄)-alkoxy groups. R₂ is further the aroyl radical, where the     aryl moiety on which this radical is based is the phenyl ring, which     can be mono- or polysubstituted by halogen, (C₁-C₆)-alkyl,     (C₃-C₇)-cycloalkyl, carboxyl groups, carboxyl groups esterified with     C₁-C₆-alkanols, trifluoromethyl groups, hydroxyl groups, methoxy     groups, ethoxy groups or benzyloxy groups.

-   R₃ and R₄ can be identical or different and are hydrogen,     (C₁-C₆)-alkyl, (C₃-C₇)-cycloalkyl, (C₁-C₆)-alkanoyl, (C₁-C₆)-alkoxy,     halogen and benzyloxy. R₃ and R₄ can furthermore be the nitro group,     the amino group, the (C₁-C₄)-mono or dialkyl-substituted amino     group, and the (C₁-C₆)-alkoxycarbonylamino function or     (C₁-C₆)-alkoxycarbonylamino-(C₁-C₆)-alkyl function.

-   Z is O and S.

The designation alkyl, alkanol, alkoxy or alkylamino group for the radicals R, R₁, R₂, R₃, R₄, R₅, R₆, R₇ is normally understood as meaning both “straight-chain” and “branched” alkyl groups, where “straight-chain alkyl groups can be, for example, radicals such as methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl and “branched alkyl groups” designate, for example, radicals such as isopropyl or tert-butyl. “Cycloalkyl” is understood as meaning radicals such as, for example, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl or cycloheptyl.

The designation “halogen” represents fluorine, chlorine, bromine or iodine. The designation “alkoxy group” represents radicals such as, for example, methoxy, ethoxy, propoxy, butoxy, isopropoxy, isobutoxy or pentoxy.

The compounds can also be employed as acid addition salts, for example as salts of mineral acids, such as, for example, hydrochloric acid, sulfuric acid, phosphoric acid, salts of organic acids, such as, for example, acetic acid, lactic acid, malonic acid, maleic acid, fumaric acid, gluconic acid, glucuronic acid, citric acid, embonic acid, methanesulfonic acid, trifluoroacetic acid, succinic acid and 2-hydroxyethanesulfonic acid.

Both the compounds of the formula 1 and their salts are biologically active.

The compounds of the formula 1 can be administered in free form or as salts with physiologically tolerable acids.

Administration can be performed orally, parenterally, intravenously, transdermally or by inhalation.

The invention furthermore relates to pharmaceutical preparations which contain at least one of the compounds of the formula 1 or their salts with physiologically tolerable inorganic or organic acids and, if appropriate, pharmaceutically utilizable excipients and/or diluents or auxiliaries.

Suitable administration forms are, for example, tablets, coated tablets, capsules, solutions for infusion or ampoules, suppositories, patches, powder preparations which can be employed by inhalation, suspensions, creams and ointments.

The processes for the production of the compounds according to the invention are described in the following reaction schemes 1 and 2 and in general procedures. All compounds can be prepared as described or analogously.

The compounds of the general formula 1 with Z=O, R₁=aryl, aralkyl, heteroaryl and heteroaralkyl and R₂=alkyl, aralkyl and heteroaralkyl are obtainable according to the following Scheme 1:

1st Stage

The indol derivative, which can be unsubstituted or monosubstituted or polysubstituted on C-2 or in the phenyl structure, is dissolved in a protic, dipolar aprotic or nonpolar organic solvent, such as, for example, isopropanol, tetrahydrofuran, dimethyl sulfoxide, dimethylformamide, dimethylacetamide, N-methylpyrrolidone, dioxane, toluene or methylene chloride and added dropwise to a suspension of a base prepared in a three-necked flask under an N₂ atmosphere or employed in a molar amount or in excess, such as, for example, sodium hydride, powdered potassium hydroxide, potassium tert-butoxide, dimethylaminopyridine or sodium amide, in a suitable solvent. Then the desired alkyl, aralkyl or heteroaralkyl halide, for example, is added, if appropriate with addition of a catalyst, such as, for example, copper and the mixture is allowed to react for some time, for example for 30 minutes to 12 hours, and the temperature is maintained within a range from 0° C. to 120° C., preferably between 30° C. to [sic] 80° C., particularly between 50° C. and 65° C. After completion of the reaction, the reaction mixture is added to water, the solution is extracted, e.g. with diethyl ether, dichloromethane, chloroform, methyl tert-butyl ether or tetrahydrofuran, and the organic phase obtained in each case is dried with anhydrous sodium sulfate. The organic phase is concentrated in vacuo, the residue which remains is crystallized by trituration or the oily residue is purified by recrystallization, distillation or by column or flash chromatography on silica gel or alumina. The eluent used is, for example, a mixture of dichloromethane and diethyl ether in the ratio 8:2 (vol/vol) or a mixture of dichloromethane and ethanol in the ratio 9:1 (vol/vol).

2nd Stage

The N-substituted indol obtained according to the above procedure of the 1st Stage is dissolved under a nitrogen atmosphere in an aprotic or nonpolar organic solvent, such as, for example, diethyl ether, methyl tert-butyl ether, tetrahydrofuran, dioxane, toluene, xylene, methylene chloride or chloroform and added to a solution prepared under a nitrogen atmosphere of a monomolar up to 60% excess amount of oxalyl chloride in an aprotic or nonpolar solvent, such as, for example, in diethyl ether, methyl tert-butyl ether, tetrahydrofuran, dioxane, toluene, xylene, methylene chloride, the temperature being kept between −5° C. and 20° C. The reaction solution is then heated at a temperature between 10° C. and 130° C., preferably between 20° C. and 80° C., particularly between 30° C. and 50° C., for a period of 30 minutes to 5 hours and the solvent is then evaporated. The residue of the “indolyl-3-glyoxyloyl chloride” formed in this manner which remains is dissolved in an aprotic solvent such as, for example, tetrahydrofuran, dioxane, diethyl ether, toluene or alternatively in a dipolar aprotic solvent, such as, for example, dimethylformamide, dimethylacetamide or dimethyl sulfoxide, cooled to a temperature between 10° C. and −15° C., preferably between −5° C. and 0° C., and treated in the presence of an acid scavenger with a solution of the primary or secondary amine in a diluent. Possible diluents are the solvents used above for dissolving the indolyl-3-glyoxyloyl chloride. Acid scavengers used are triethylamine, pyridine, dimethylaminopyridine, basic ion exchanger, sodium carbonate, potassium carbonate, powdered potassium hydroxide and excess primary or secondary amine employed for the reaction. The reaction takes place at a temperature from 0° C. to 120° C., preferably at 20-80° C., particularly between 40° C. and 60° C. After a reaction time of 1-3 hours and standing at room temperature for 24 hours, the hydrochloride of the acid scavenger is filtered, the filtrate is concentrated in vacuo and the residue is recrystallized from an organic solvent or purified by column chromatography on silica gel or alumina. Eluents used are, for example, a mixture of dichloromethane and ethanol (95:5, vol/vol).

WORKING EXAMPLES

According to this general procedure for Stages 1 and 2, on which synthesis scheme 1 is based, the following compounds were synthesized which are evident from the following tabulated list detailing the respective chemical name. In Tables 1a-j on pages A-J, the structures of these compounds and their melting points can be seen from the general formula 1 and the substituents R₁-R₄ and Z:

Example 1 N-(Pyridin-4-yl)-[1-(4-fluorobenzyl)indol-3-yl}glyoxyl-amide (D 24241)

1st Stage

1-(4-Fluorobenzyl)indole

A solution of 11.72 g (0.1 mol) of indol in 50 ml of dimethyl sulfoxide is added to a mixture of 2.64 g of sodium hydride (0.11 mol, mineral oil suspension) in 100 ml of dimethyl sulfoxide. The mixture is heated at 60° C. for 1.5 hours, then allowed to cool and 15.9 g (0.11 mol) of 4-fluorobenzyl chloride are added dropwise. The solution is warmed to 60° C., allowed to stand overnight and then poured into 400 ml of water with stirring. The mixture is extracted a number of times with a total of 150 ml of methylene chloride, the organic phase is dried using anhydrous sodium sulfate, filtered and the filtrate is concentrated in vacuo. The residue is distilled in a high vacuum: 21.0 g (96% of theory) b.p. (0.5 mm): 140° C.

2nd Stage

N-(Pyridin-4-yl)-[1-(4-fluorobenzyl)indol-3-yl]glyoxyl-amide (D 24241)

A solution of 4.75 g (21.1 mmol) of 1-(4-fluoro-benzyl)indol in 25 ml of ether is added dropwise at 0° C. and under N₂ to a solution of 2.25 ml of oxalyl chloride in 25 ml of ether. The mixture is heated to reflux for 2 hours and the solvent is then evaporated. 50 ml of tetrahydrofuran were then added to the residue, the solution was cooled to −5° C. and treated dropwise with a solution of 4.66 g (49.5 mmol) of 4-aminopyridine in 200 ml of THF. The mixture is heated to reflux for 3 hours and allowed to stand at room temperature overnight. The 4-aminopyridine hydro-chloride is filtered off with suction, the precipitate is washed with THF, the filtrate is concentrated in vacuo and the residue is recrystallized from ethyl acetate.

Yield: 7.09 g (90% of theory)

Melting point: 225-226° C.

Elemental Analysis:

ber. C 70.77 H 4.32 N 11.25 gef. C 71.09 H 4.36 N 11.26 Example 2, D 24242 N-(Pyridin-4-yl)-(1-methylindol-3- yl)glyoxylamide Example 3, D 24834 N-(Pyridin-3-yl)-[1-(4-fluoro- benzyl)indol-3-yl]glyoxylamide Example 4, D 24835 N-(Pyridin-3-yl)-(1-benzylindol- 3-yl)glyoxylamide Example 5, D 24836 N-(Pyridin-3-yl)-[1-(2-chloro- benzyl)indol-3-yl]glyoxylamide Example 6, D 24840 N-(4-Fluorophenyl)-[1-(4-fluoro- benzyl)indol-3-yl]glyoxylamide Example 7, D 24841 N-(4-Nitrophenyl)-[1-(4-fluoro- benzyl)indol-3-yl]glyoxylamide Example 8, D 24842 N-(2-Chloropyridin-3-yl)-[1-(4- fluorobenzyl)indol-3-yl]glyoxyl- amide Example 9, D 24843 N-(Pyridin-4-yl)-(1-benzylindol- 3-yl)glyoxylamide Example 10, D 24848 N-(Pyridin-4-yl)-[1-(3-pyridyl- methyl)indol-3-yl]glyoxylamide Example 11, D 24849 N-(4-Fluorophenyl)-[1-(2-pyridyl- methyl)indol-3-yl]glyoxylamide Example 12, D 24850 N-(4-Fluorophenyl)-[1(3-pyridyl- methyl)indol-3-yl]glyoxylamide Example 13, D 24851 N-(Pyridin-4-yl)-[1-(4-chloro- benzyl)indol-3-yl]glyoxylamide Example 14, D 24852 N-(Pyridin-4-yl)-[1-(2-chloro- benzyl)indol-3-yl]glyoxylamide Example 15, D 24853 N-(Pyridin-2-yl)-[1-(4-fluoro- benzyl)indol-3-yl]glyoxylamide Example 16, D 24847 N-(Pyridin-4-yl)-[1-(2-pyridyl- methyl)indol-3-yl]glyoxylamide Example 17, D 24858 (4-Phenylpiperazin-1-yl)-[1-(4- fluoropenzyl)indol-3-yl]glyoxyl- amide Example 18, D 24854 N-(Pyridin-2-yl)-(1-benzylindol- 3-yl)glyoxylamide Example 19, D 25421 N-(Pyridin-4-yl)-[1-(4-fluoro- benzyl)-6-ethoxycarbonylamino- indol-3-yl]glyoxylamide Example 20, D 25422 N-(Pyridin-4-yl)-[1-(4-fluoro- benzyl)-5-ethoxycarbonylamino- indol-3-yl]glyoxylamide Example 21, D 25423 N-(Pyridin-4-yl)-[1-(4-fluoro- benzyl)-6-cyclopentyloxycarbonyl- aminoindol-3-yl]glyoxylamide Example 22, D 25420 4-(Pyridin-4-yl)piperazin-1-yl)- [1-(4-fluorobenzyl)indol-3-yl]- glyoxylamide Example 23, D 24866 N-(3,4,5-Trimethoxybenzyl)- N-(allylaminocarbonyl- 2-methylprop-1-yl)-[1-(4- fluorobenzyl)indol-3-yl]glyoxyl- amide Example 24 N-(Pyridin-4-yl)-[1-(4-fluoro- benzyl)-5-methoxyindol-3-yl]- glyoxylamide Example 25 N-(Pyridin-4-yl)-[1-(4-fluoro- benzyl)-5-ethoxycarbonylamino- methylindol-3-yl]glyoxylamide

Starting Substances for the Compounds of the General Formula 1 Prepared According to Synthesis Scheme 1, which are Evident from Table 1.

For the synthesis final products

D 24241 D 24242 D 24834 D 24835 D 24836 D 24840 D 24841 D 24842 D 24843 D 24848 D 24849 D 24850 D 24851 D 24852 D 24853 D 24847 D 24858 D 24854 D 25420 D 25422 D 25421 D 25423 all precursors are commercially available.

Furthermore, the compounds of the general formula 1 with Z=0, R₁=aryl, aralkyl, heteroaryl, heteroaralkyl and the allylamino-carbonyl-2-methylprop-1-yl group and R₂=alkyl, aralkyl and the heteroaralkyl group are also obtainable according to the synthesis route of Scheme 2:

The compounds D 24241, D 24841, D 24840 and D 24834 (2nd Stage of reaction scheme 2, see also Table 1) and their respective precursors D 24825, D 24831, D 24832 and D 24833 (1st Stage of reaction scheme 2, see also Table 2 on page K) were obtained according to the present Scheme 2.

N-(Pyridin-4-yl)-[1-(4-fluorobenzyl)indol-3-yl]-glyoxylamide (D 24241)

1st Stage

N-(Pyridin-4-yl)-(indol-3-yl)glyoxylamide

A solution of 10 g (85.3 mmol) of indole in 100 ml of ether is added dropwise at 0° C. to a solution of 9 ml of oxalyl chloride in 100 ml of anhydrous ether. The mixture is kept under reflux for 3 hours. A suspension of 12 g (127.9 mmol) of 4-aminopyridine in 500 ml of tetrahydrofuran is then added dropwise at −5° C., the reaction mixture is heated to reflux temperature with stirring for 3 hours and allowed to stand overnight at room temp. It is filtered, the precipitate is treated with water and the dried compound is purified on a silica gel column (silica gel 60, Merck AG, Darmstadt) using the eluent methylene chloride/ethanol (10:1, v/v).

Yield: 9.8 g (43.3% of theory) M.p.: from 250° C.

2nd Stage:

N-(Pyridin-4-yl)-[1(4-fluorobenzyl)indol-3-yl]-glyoxylamide (D 24241) The N-(pyridin-4-yl)-(indol-3-yl)glyoxylamide obtained according to the 1st Stage is reacted with 4-fluorobenzyl chloride according to the “benzylation procedure” (page 5) and the compound D 24241 obtained is isolated.

Yield: 41% of theory

M.p.: 224-225° C.

Elemental Analysis:

calc. C 70.77 H 4.32 N 11.25 found C 70.98 H 4.40 N 11.49

General Procedure for the Preparation of the Compounds of the General Formula 1 According to Scheme 2

1st Stage:

The indol derivative, which can be unsubstituted or substituted on C-2 or in the phenyl ring, dissolved in a solvent, as, for example, indicated above for oxalyl chloride, is added dropwise at a temperature between −5° C. and +5° C. to a solution prepared under a nitrogen atmosphere of a monomolar up to 60% excess amount of oxalyl chloride in an aprotic or nonpolar solvent, such as, for example, in diethyl ether, methyl tert-butyl ether, tetrahydrofuran, dioxane or alternatively dichloromethane. The reaction solution is then heated for 1 to 5 hours to a temperature between 10° C. and 120° C., preferably between 20° C. and 80° C., particularly between 30° C. and 60° C., and the solvent is then evaporated. The residue of the (indol-3-yl)glyoxyloyl chloride which remains is dissolved or suspended in an aprotic solvent, such as, for example, tetrahydrofuran, dioxane, diethyl ether, toluene or alternatively in a dipolar aprotic solvent, such as, for example, dimethylformamide, dimethylacetamide or dimethyl sulfoxide, cooled to a temperature between −10° C. and +10° C., preferably to −5° C. to 0° C., and treated in the presence of an acid scavenger with a solution of the primary or secondary amine in a diluent. Possible diluents are the solvents used for dissolving the “indolyl-3-glyoxyloyl chloride”. Acid scavengers used are triethylamine, pyridine, dimethylaminopyridine, basic ion exchanger, sodium carbonate, potassium carbonate, powdered potassium hydroxide and excess primary or secondary amine employed for the reaction.

The reaction takes place at a temperature from 0° C. to 120° C., preferably at 20-80° C., particularly between 40° C. and 60° C. After a reaction time of 1-4 hours and standing at room temperature for 24 hours, the mixture is filtered, the precipitate is digested with water, filtered off with suction and dried in vacuo. The desired compound is purified by recrystallization in an organic solvent or by column chromatography on silica gel or alumina. The eluent used is, for example, a mixture of dichloromethane and ethanol (10:1, vol/vol).

2nd Stage

The “indol-3-ylglyoxylamide” obtained according to the above procedure of the 1st Stage is dissolved in a protic, dipoplar aprotic or nonpolar organic solvent, such as, for example, in isopropanol, tetrahydrofuran, dimethyl sulfoxide, dimethylformamide, dimethylacetamide, N-methylpyrrolidone, dioxane, toluene or methylene chloride and added dropwise to a suspension of a base prepared in a three-necked flask under an N₂ atmosphere or employed in a molar amount or in excess, such as, for example, sodium hydride, powdered potassium hydroxide, potassium tert-butoxide, dimethylaminopyridine or sodium amide in a suitable solvent. The desired alkyl, aralkyl or heteroaralkyl halide is then added either undiluted or in a diluent, which was also used, for example, for dissolving the “indol-3-ylglyoxylamide”, if appropriate with addition of a catalyst, such as, for example, copper and the mixture is allowed to react for some time, e.g. for 30 minutes to 12 hours, and the temperature is kept within a range between 0° C. and 120° C., preferably between 30° C. and 80° C., particularly between 50 and 70° C. After completion of the reaction, the reaction mixture is added to water, the solution is extracted, for example, with diethyl ether, dichloromethane, chloroform, methyl tert-butyl ether, tetrahydrofuran or n-butanol and the organic phase obtained in each case is dried using anhydrous sodium sulfate.

The organic phase is concentrated in vacuo, the residue which remains is crystallized by trituration or the oily residue is purified by distillation or by column or flash chromatography on silica gel or alumina. The eluent used is, for example, a mixture of methylene chloride and diethyl ether in the ratio 8:2 (vol/vol) or a mixture of methylene chloride and ethanol in the ratio 9:1 (v/v)

According to this general procedure for stages 1 and 2, on which the synthesis scheme 2 is based, the compounds D 24241, D 24841, D 24840 and D 24834 were synthesized, which have also already been prepared according to the synthesis procedure of reaction scheme 1 and are evident from Table 1. The relevant precursors of these compounds can be seen from Table 2 on page K and L.

The compounds show a good dose-dependent antitumor action in the following pharmacological models:

-   -   The indoles, particularly D-24851 and D-24241, are first         apparent in the XTT proliferation test/cytotoxicity test (Table         3 and Table 3a). In this test system, the effect of substances         on the proliferation behavior of tumor cell lines is         investigated. In the course of this, the cytotoxic potential of         these substances is determined. The test method is described in         Scudiero et al. 1988, Cancer Res. 48, 4827.

The following tumor cell lines were employed in the investigations:

The KB cell line an epidermal carcinoma of the oral cavity,

the L1210 cell line a lymphatic leukemia of the mouse, the LNCAP cell line a prostate carcinoma and the SK-OV-3 cell line an ovarian carcinoma.

A large number of different indols were active in all four tumor cell lines. D-24851 and D-24241 showed the strongest actions, D-24851 being more active than D-24241 (Table 3 and 4).

In further comparative investigations with D-24851 and D-24241 in the hollow fiber assay on the nude mouse and on L 1210 (mouse), a strong dose-dependent antitumor action was observed for both compounds (Table 3 and 5). In the hollow fiber assay, both compounds were almost equally strongly active, while on L 1210 D-24851 was markedly more strongly active after oral and intraperitoneal administration than D-24241. In comparison with the antitumor substances available on the market, D-24851 is markedly more strongly active in many cases in the leukemia model than the known comparison substances (Table 5).

A further great advantage of D-24851 in comparison with the antitumor substances available on the market is the low toxicity of the compound (Tables 3 and 5). With LD 50 values of 1000 mg/kg p.o. and >1000 mg/kg i.p., the compound has a great therapeutic breadth. Furthermore, after administration of D-24851 no DNA fragmentation was observed. In the hematopoiesis test, too, none of the blood parameters investigated were modified by the intraperitoneal administration of D-24851.

In a further chemotherapy model, the Dunning tumor in the rat, a stoppage of tumor growth and in some animals even tumor regression was observed after repeated oral administration of D24851.

In the KB test on the nude mouse, an antitumor action was likewise observed after administration of the two indols D-24851 and D-24241 (Tables 3, 3a and 4).

In the investigations with the tumor cell line L1210, a lymphatic leukemia of the mouse, a distinct dose-dependent prolongation of the survival time was seen after intraperitoneal or oral administration of D 24851 with a 100 and 147 mg/kg multiple dose (FIG. 1 a and FIG. 1 b).

On account of the good therapeutic breadth, which was demonstrated experimentally, the active substance can be administered in a higher amount than commercially available tumor pharmaceuticals.

Without wishing to restrict the scope of the invention by the following details, it can be said that doses from approximately 20 mg up to 500 mg daily are possible orally. In the case of intravenous administration as an injection or as an infusion, up to 250 mg/day or more can be administered depending on the body weight of the patient and individual tolerability.

TABLE 3 Composition D-24851 according to Example 13 D-24851 N-(Pyridin-4-yl)-[1-(4-chlorobenzyl)indol-3-yl]glyoxylamide Model Result. SK-OV-3 KB L1210 LNCaP MCF-7 Tox XTT (μg/ml) EC₅₀ ≈0.03 ≈0.017 ≈0.017 ≈0.03 1 × ip (mg/kg) LD₅₀ =1000 1 × per os (mg/kg) LD₅₀ >1000 Hollow fiber intra- % INH no 56 38 peritoneal action 4 × 46 mg/kg ip Hollow fiber intra- % INH 12 60 68 peritoneal 4 × 147 mg/kg ip Hollow fiber subcuta- % INH 44 no action 47 neous 4 × 46 mg/kg ip Hollow fiber subcuta- % INH 35 67 68 neous 4 × 147 mg/kg ip In vivo: 1 × 681 mg/kg ip % ILS 0 1 × 464 mg/kg ip 18 4 × 215 mg/kg ip % ILS 13 4 × 147 mg/kg ip 94 7 × 100 mg/kg ip % ILS 35 7 × 147 mg/kg ip 59 1 × 681 mg/kg po % ILS 22 4 × 215 mg/kg po 31 7 × 100 mg/kg po 63 7 × 147 mg/kg po 75 7 × 46 mg/kg ip % WHI 33 2 × 215 mg/kg po 18

TABLE 3a Substance according Tumor cells XTT to Example KB L 1210 LNCAP SK-OV-3 (D Number) EC₅₀ [μg/ml] EC₅₀ [μg/ml] EC₅₀ [μg/ml] EC₅₀ [μg/ml]  1 (D 24241) 0.020 0.170 >31.600 0.170  3 (D 24834) 1.75 1.75 9.250 1.750  4 (D 24835) 17.5 1.750 >31.6 9.200  6 (D 24840) 3.100 1.750 >31.6 17.5  9 (D 24843) 0.050 0.090 3.240 1.750 10 (D 24848) 4.060 1.75 >31.6 7.220 11 (D 24849) 4.590 1.750 17.500 4.250 12 (D 24850) >31.6 0.017 >31.6 >31.6 13 (D 24851) 0.017 0.017 0.030 0.030 14 (D 24852) 1.75 1.75 17.5 2.58 15 (D 24853) >31.6 3.1 >31.6 >31.6 16 (D 24847) 4.59 1.75 17.500 4.250 Table 2 17.5 17.5 17.5 17.5 (D 24831)

Further Animal Experimental Results:

Stoppage of tumor growth, in some animals even tumor regression, was observed in the Dunning tumor after administration of 7×100 mg/kg and 7×147 mg/kg p.o. of D-24851.

In comparison with the original form, the testing of the crystalline form yielded no differences.

D-24851 causes no DNA fragmentation

In the hematopoiesis test, none of the blood parameters investigated were altered by the intraperitoneal administration of D-24851.

TABLE 4 D 24241 N-(Pyridin-4-yl)-[1-(4-fluorobenzyl)indol-3-yl]glyoxylamide according to Example 1 Model Result. SK-OV-3 KB L1210 LNCaP MCF-7 Tox XTT (μg/ml) EC₅₀ ≈0.17 ≈0.02 ≈0.17 >31.6 1 × ip (mg/kg) LD₅₀ ≈158 1 × per os (mg/kg) LD₅₀ >1000 Hollow fiber intra- % INH 46 43 no action peritoneal 4 × 15.8 mg/kg ip Hollow fiber sub- % INH 81 68 33 cutaneous 4 × 15.8 mg/kg ip In vivo: 1 × 14.7 mg/kg ip % ILS no action 1 × 30 mg/kg per os % ILS no action 1 × 464 mg/kg per os % ILS 44 4 × 30 mg/kg per os % ILS no action 6 × 30 mg/kg per os % ILS no action 14 × 30 mg/kg per os % ILS no action 19 × 50 mg/kg per os % ILS 50 2 × 46.4 mg/kg ip % WHI 22 4 × 21.5 mg/kg ip % WHI no action 2 × 215 mg/kg po % WHI 47

TABLE 5 Comparison of the antitumor action of D-24851 and D-24241 with standard compounds XTT Tox. L1210 EC 50 Substance mg/kg mg/kg (μg/ml) D-24851 ≈1000 i.p. 4 × 147 i.p. KB ≈ 0.017 94% ILS L1210 ≈ 0.017 SKOV3 ≈ 0.03 LNCAP ≈ 0.03 D-24241 ≈158 i.p. 19 × 50 p.o. KB ≈ 0.02 50% ILS L1210 ≈ 0.07 SKOV3 ≈ 0.17 LNCAP > 31.6 Mitoxantrone 16 i.v. 1 × 4.64 i.v. KB ~ 0.174 144% ILS L1210 < 0.0003 SKOV3 ~ 0.174 LNCAP ~ 0.017 5-Fluorouracil — 1 × 147 i.p. — 72% ILS 4 × 68.1 i.p. 83% ILS Methotrexate — 1 × 53.7 i.p. KB ~ 0.007 39% ILS L1210 n.d. SKOV3 > 31.6 LNCAP n.d. Etoposide ≈158.0 i.p. 1 × 46.4 i.p. — >68.1 i.v. 56% ILS Ratjadone ~16.0 1 × 1.47 i.p. KB < 0.003 i.p. 22% ILS L1210 < 0.003 ~30.0 i.v. SKOV3 < 0.003 LNCAP < 0.003 Epothilone B ≈100.0 i.p. 1 × 10 i.p. KB ~ 0.0002 44% ILS L1210 ~ 0.0017 SKOV3 ~ 0.0031 LNCAR ~ 0.014 Taxol ≈158 i.p. 1 × 14.7 i.v. KB < 0.003 22% ILS L1210 < 0.003 1 × 46.4 i.v. SKOV3 < 0.003 61% ILS LNCAP < 0.003 Vincristine ≈3.0 i.v. 1 × 1.0 i.p. KB < 0.001 29% ILS L1210 0.004 SKOV3 0.003 LNCAP 0.004 Adriamycin ≈27.0 i.v. 1 × 14.7 i.v. KB 0.15 111% ILS L1210 0.174 SKOV3 0.089 LNCAP 0.17 Cisplatin ≈16.0 i.p. 1 × 3.16 i.p. L1210 0.30 ≈73.0 p.o. 38.9% ILS Carboplatin ≈158.0 1 × 100 i.p. — i.p. 41% ILS ≈841.0 p.o Lobaplatin ≈34.0 i.p. 1 × 14.7 i.p. — 55.0% ILS Cyclophosph- ≈340.7 i.v. 1 × 46.4 i.v. — amide 40% ILS Ifosfamide ≈732 i.p. 1 × x 316 i.p. — 89% ILS Miltefosine ≈46.4 i.p. no action — ≈464-1000 p.o.

TABLE 1a Formula 1

Indolylglyoxylamides according to reaction scheme 1 Example D R R₁ R₂ R₃ R₄ Z M.p. 1 D-24241 H

H H O 225-6° C. 2 D-24242 H

CH₃ H H O 176° C. 3 D-24834 H

H H O 173° C. 4 D-24835 H

H H O 140° C. 5 D-24836 H

H H O 185° C.

TABLE 1b Indolylglyoxylamides according to reaction scheme 1 Example R R₁ R₂ R₃ R₄ Z M.p. 6 D-24840 H

H H O   199° C. 7 D-24841 H

H H O >250° C. 8 D-24842 H

H H O   149° C. 9 D-24843 H

H H O 178-180° C. 10 D-24848 H

H H O   179° C. 11 D-24849 H

H H O   132° C.

TABLE 1c Indolylglyoxylamides according to reaction scheme 1 Example D R R₁ R₂ R₃ R₄ Z M.p. 12 D-24850 H

H H O 144° C. 13 D-24851 H

H H O 262° C. 14 D-24852 H

H H O 184° C. 15 D-24853 H

H H O 141° C. 16 D-24847 H

H H O 202° C. 17 D-24858

H H O 115° C. 18 D-24854 H

H H O 112-3° C.

TABLE 1d Indolylglyoxylamides according to reaction scheme 1 Ex- ample D R R₁ R₂ R₃ R₄ Z M.p. 19 D- 25421 H

6-NHCOOEt H O >250° C. 20 D- 25422 H

5-NHCOOEt H O   183° C. 21 D- 25423 H

H O 22 D- 25420

H H O 160-62° C.  23 D- 24866

H H O 139-141° C. 24 D- 25561 H

5-OCH₃ H O   188° C. 25 D- 25559 H

5-CH₂—NHCOOEt H O 175-176° C.

TABLE 1e Indole-3-glyoxylic acid derivative according to reaction scheme 1 Formula 1

Example, D- R R₁ R₂ R₃ R₄ Z M.p. 26 D-50570 H

H H O 27 D-51076 H

H H O 28 D-49404 H

5-F H O 205-207° C. 29 D-44073 H

H H O 192-194° C. 30 D-44072 H

H H O 196-198° C. 31 D-44067 H

H H O 219-221° C.

TABLE 1f Indole-3-glyoxylic acid derivative according to reaction scheme 1 Example, D- R R₁ R₂ R₃ R₄ Z M.p. 32 D-44061 H

H H O 238-240° C. 33 D-43163 H

H H O 203-205° C. 34 D-51273 H

H H O 305-307° C. 35 D-44070 H

H H O >250° C. 36 D-49405 H

H H O 237-239° C. 37 D-44071 H

H H O 154-156° C. 38 D-44069 H

H H O 213-215° C. 39 D-44068 H

H H O 183-185° C.

TABLE 1g Indole-3-glyoxylic acid derivative according to reaction scheme 1 Example, D- R R₁ R₂ R₃ R₄ Z M.p. 40 D-44066 H

H H O 187-189° C. 41 D-49406 H

H O 191-193° C. 42 D-49403 H

H O 193-195° C. 43 D-44064 H

H H O 104-106° C. 44 D-43156 H

6-NO₂ H O 238-240° C. 45 D-43155 H

5-NO₂ H O 203-205° C. 46 D-43152 H

H H O 196-198° C. 47 D-43151 H

H H O 141-143° C.

TABLE 1h Indole-3-glyoxylic acid derivative according to reaction scheme 1 Example, D- R R₁ R₂ R₃ R₄ Z M.p. 48 D-43149 H

H H O 202-204° C. 49 D-43148 H

H H O 183-185° C. 50 D-25505 hydro- chloride H

H H O Hydrochlorid 51 D-51133 trifluoro- acetate H

H H O 251-253° C. Trifluoracetat 52 D-51128 H

H H O 173-174° C. 53 D-51077 H

H H O 244-245° C. 54 D-51195 H

H O 228-230° C. 55 D-51391 H

H H O 270-271° C.

TABLE 1i Indole-3-glyoxylic acid derivative according to reaction scheme 1 Example, D- R R₁ R₂ R₃ R₄ Z M.p. 56 D-51393 H

H H O Öl 57 D-51394 H

H H O 216-218° C. 58 D-51184 H

H H O 215-217° C. 59 D-51185 H

H H O 241-242° C. 60 D-25463 H

H H O ° C. 61 D-24584 H

H H O ° C. 62 D-25320 H

H H O 145-147° C.

TABLE 1j Indole-3-glyoxylic acid derivative according to reaction scheme 1 Example, D- R R₁ R₂ R₃ R₄ Z M.p. 63 D-51396

H H O 137° C. 64 D-44065

H H O 205-207° C. 65 D-43146

H H O 89-91° C. 66 D-43145

H H O 68-70° C. 67 D-25558

6-NHCOOC₂H₅ H O oil

TABLE 2 Indolylglyoxylamides according to reaction scheme 2 Formula 1

Ex- ample, D- R R₁ R₂ R₃ R₄ Z M.p. 1 D-24825 H

H H H O >250° C. 2 D-24831 H

H H H O >250° C. 3 D-24832 H

H H H O 233-5° C. 4 D-24833 H

H H H O 235° C.

TABLE 2a Indolylglyoxylamides according to reaction scheme 2 Ex- ample, D- R R₁ R₂ R₃ R₄ Z M.p. 5 D-43154 H

H 6-NO₂ H O 250° C. (dec.) 6 D-43153 H

H 5-NO₂ H O >250° C. 7 D-25319 H

H H H O 156- 157° C.

TABLE 2b Indol-3-glyoxylic acid derivatives according to reaction scheme 1 Ex- ample, D- R R₁ R₂ R₃ R₄ Z M.p. 5 D-43154 H

H 6-NO₂ H O 250° C. (dec) 6 D-43153 H

H 5-NO₂ H O >250° C. 7 D-25319 H

H H H O 156- 157° C. 

1. A method of treating a disease selected from leukemia, prostate carcinoma, ovarian carcinoma, epidermal carcinoma, and dunning tumor, the method comprising administering to a subject in need thereof an effective amount of N-substituted indole-3-glyoxylamide of formula I

or an acid addition salt thereof wherein the radicals R, R₁, R₂, R₃, R₄, and Z have the following meanings: R=hydrogen, (C₁-C₆)-alkyl, where the alkyl group is optionally mono- or polysubstituted by a phenyl ring and this phenyl ring is optionally substituted by one or more substituents selected from halogen, (C₁-C₆)-alkyl, (C₃-C₇)-cycloalkyl, a carboxyl group, a carboxyl group esterified with a (C₁-C₆)-alkanol, a trifluoromethyl group, a hydroxyl group, a methoxy group, an ethoxy group, a benzyloxy group, or a benzyl group which is mono- or polysubstituted in the phenyl moiety by one or more substituents selected from (C₁-C₆)-alkyl group, a halogen, and a trifluoromethyl group, or R=a benzyloxycarbonyl group or a tertiary-butoxycarbonyl radical, or an acetyl group, R₁=a pyridine structure of formula II

or its N-oxide, where the pyridine structure is bonded at either the 2, 3, or 4 position of the ring and is optionally substituted by R₅ and R₆; wherein R₅ and R₆ are identical or different and are selected from (C₁-C₆)-alkyl, (C₃-C₇)-cycloalkyl, (C₁-C₆)-alkoxy, nitro, amino, hydroxyl, halogen, trifluoromethyl, ethoxycarbonylamino radical and a carboxyalkyloxy group in which the alkyl group has 1-4 C atoms; R₂=hydrogen or (C₁-C₆)-alkyl, where the alkyl group is mono- or polysubstituted by halogen or phenyl, which is optionally substituted by one or more substituents selected from halogen, (C₁-C₆)-alkyl, (C₃-C₇)-cycloalkyl, a carboxyl group, a carboxyl group esterified with a (C₁-C₆)-alkanol, a trifluoromethyl group, a hydroxyl group, a methoxy group, an ethoxy group or a benzyloxy group, wherein when R₂ is a (C₁-C₆)-alkyl group, it is optionally substituted by a 2-quinolyl group where the 2-, 3- and 4-pyridyl structure, is optionally mono- or polysubstituted by one or more substituents selected from halogen, (C₁-C₄)-alkyl groups or (C₁-C₄)-alkoxy groups, or R₂ is an aroyl radical, where the aryl moiety on which the radical is based is a phenyl ring, which is optionally mono- or polysubstituted by halogen, (C₁-C₆)-alkyl, (C₁-C₆)-cycloalkyl, a carboxyl group, a carboxyl groups esterified with a (C₁-C₆)-alkanol, trifluoromethyl group, a hydroxyl group, a methoxy group, an ethoxy group or a benzyloxy group; R₃ and R₄ are identical or different and are independently selected from hydrogen, (C₁-C₆)-alkyl, (C₃-C₇)-cycloalkyl, (C₁-C₆)-alkanoyl, (C₁-C₆)-alkoxy, halogen, benzyloxy, a nitro group, an amino group, a (C₁-C₄)-mono or dialkyl-substituted amino group, a (C₁-C₆) alkoxycarbonylamino, and —(C₁-C₆)-alkoxycarbonylamino-(C₁-C₆)-alkyl; and Z is oxygen or sulfur.
 2. The method of claim 1, wherein said N-substituted indole-3-glyoxylamide is of the formula 1a

wherein R, R₃ and R₄=hydrogen; R₁=4-pyridyl; R₂=benzyl, 4-bromobenzyl, 4-chlorobenzyl, 4-fluorobenzyl, or 3-pyridylmethyl; and Z=oxygen.
 3. The method of claim 1, wherein an acid addition salt is administered, which salt is the salt of a mineral acid, hydrochloric acid, sulfuric acid, phosphoric acid, or a salt of an organic acid, or N-oxide thereof.
 4. The method of claim 3, wherein the organic acid is selected from acetic acid, lactic acid, malonic acid, fumaric acid, gluconic acid glucuronic acid, citric acid, embonic acid, methanesulfonic acid, trifluoroacetic acid, succinic acid, and 2-hydroxy-ethanesulfonic acid.
 5. The method of claim 1, wherein the disease is prostate carcinoma.
 6. The method of claim 1, wherein the disease is ovarian carcinoma.
 7. The method of claim 1, wherein the disease is epidermal carcinoma.
 8. The method of claim 1, wherein the disease is dunning tumor.
 9. The method of claim 1, wherein the N-substituted indole-3-glyoxylamide is administered orally.
 10. The method of claim 1, wherein the N-substituted indole-3-glyoxylamide is administered intravenously.
 11. The method of claim 1, wherein the N-substituted indole-3-glyoxylamide is administered transdermally.
 12. The method of claim 1, wherein the N-substituted indole-3-glyoxylamide is administered by inhalation.
 13. The method of claim 1, wherein the disease is leukemia. 